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Appendix A: EPA Emission Standards

Table A-1: Heavy-Duty Diesel Vehicle Emission Standards

Emission Standards (grams/brake horsepower-hour)
Model Year Hydrocarbons (HC) Carbon Monoxide (CO) Nitrogen Oxides (NOx) Particulate Matter (PM)
1974-78a - 40 - -
1979-83b 1.5 25 - -
1984-87 1.3 15.5 10.7 -
1988-89 1.3 15.5 10.7 0.6
1990 1.3 15.5 6 0.6
1991-93 1.3 15.5 5 0.25
1994-97 1.3 15.5 5 0.1
1998-2003 1.3 15.5 4 0.1
2004-2006c,d 0.5 15.5 2 0.1
2007+ 0.14 15.5 0.2 0.01

Note a: Combined HC+NOx standard of 16 g/bhp-hr
Note b: Combined HC+NOx standard of 10 g/bhp-hr
Note c: Under a consent decree with U.S. EPA, engine makers implemented the 2004 standards in October 2002
Note d: Standards allow the option of 2.4 g/bhp-hr NMHC+NOx, or 2.5 g/bhp-hr NMHC+NOx and 0.5 NMHC
Source: http://www.dieselnet.com/standards/us/hd.html

Table A-2: U.S. Emission Baseline and Standards for Locomotives

  Emissions (g/bhp-hr)
  NOx PM-10
Est. 1990 Baseline Levels (unregulated)
  Line-haul duty-cycle 13.0 0.32
  Switch duty-cycle 17.4 0.44
Tier 0 (1973 - 2001 model years)
  Line-haul duty-cycle 9.5 0.60
  Switch duty-cycle 14.0 0.72
Tier 1 (2002 - 2004 model years)
  Line-haul duty-cycle 7.4 0.45
  Switch duty-cycle 11.0 0.54
Tier 2 (2005 and later model years)
  Line-haul duty-cycle 5.5 0.20
  Switch duty-cycle 8.1 0.24

Source: U.S. EPA, Locomotive Emission Standards, Regulatory Support Document, April 1998.

Table A-3: Marine Vessel Emission Standards


Emission Standards (g/kW-hr)

Engine Category

Power

Displacement

Year

HC+NOx

PM

CO

Category 1

kW > 37

L/cy < 0.9

2005+

7.5

0.4

5.0



0.9 < L/cy < 1.2

2004+

7.2

0.3

5.0



1.2 < L/cy < 2.5

2004+

7.2

0.2

5.0



2.5 < L/cy < 5.0

2007+

7.2

0.2

5.0

Category 2


All Cat. 2

2004-06

IMO stds

-

-



5.0 < L/cy < 15

2007+

7.8

0.27

5.0


kW < 3300

15 < L/cy < 20

2007+

8.7

0.5

5.0


kW > 3300

15 < L/cy < 20

2007+

9.8

0.5

5.0



20 < L/cy < 25

2007+

9.8

0.5

5.0



25 < L/cy < 30

2007+

11.0

0.5

5.0

Category 3


L/cy > 30

2004+

IMO stds

-

-

Note: IMO standards are defined as follows:

if rpm > 2000

NOx = 9.8 g/kW-hr


if 130 < rpm < 2000

NOx = 45 x rpm^(-0.2) g/kW-hr


if rpm < 130

NOx = 17 g/kW-hr

Source: “Marine Diesel Engine Emission Control Programs,” presentation by Jean Marie Revelt, U.S. EPA, January 29, 2004.

Table A-4: Aircraft Emissions Standards (gas turbine engines)


Applicability

Pollutant

Standard

Rated Pressure Ratio

Rated Output

Year of Manuf.

CO

118 g/kN (rated output)

All

All

All

NOx

(40 + 2(rated pressure ratio))g/kN(rated output)

All

All

1997-1999

NOx

(32 +1.6(rated pressure ratio))g/kN(rated output)

All

All

2000-2003

NOx

(37.572 + 1.6(rated pressure ratio) – 0.2087(rated output))g/kN (rated output)

30 or less

26.7 - 89 kN

2004+

NOx

(19 + 1.6(rated pressure ratio)) g/kN(rated output)

30 or less

> 89 kN

2004+

NOx

(42.71 + 1.4286(rated pressure ratio) - 0.4013(rated output) + 0.00642(rated pressure ratio -rated output)) g/kN(rated output)

30 - 62.5

26.7 - 89 kN

2004+

NOx

(7 + 2(rated pressure ratio) g/kN (rated output)

30 - 62.5

> 89 kN

2004+

NOx

32 + 1.6(rated pressure ratio) g/kN (rated output)

greater than 62.5

All

2004+

Note: Table does not reflect the latest NOx emissions standard as agreed at the sixth meeting of ICAO Committee on Aviation Environmental Protection (CAEP) in February 2004, which have not been promulgated by U.S. EPA regulations.
Source: U.S. EPA and the International Civil Aviation Organization.

Table A-5: EPA Non-Road Diesel Equipment Emission Standards

Engine Power Tier Starting Model Year Emission Standards (g/bhp-hr)
      NMHC+NOx NOx CO PM
hp < 11 1 2000 7.8   6.0 0.75
  2 2005 5.6   6.0 0.60
11 < hp < 25 1 2000 7.1   4.9 0.60
  2 2005 5.6   4.9 0.60
hp < 25 4 2008 5.6     0.3
25 < hp < 50 1 1999 7.1   4.1 0.60
  2 2004 5.6   4.1 0.45
25 < hp < 75 4 2013 3.5     0.02
50 < hp < 100 2 2004 5.6   3.7 0.30
  3 2008 3.5   3.7 0.30
100 < hp < 175 2 2003 4.9   3.7 0.22
  3 2007 3.0   3.7 0.22
75 < hp < 175 4 2012   0.3   0.01
175 < hp < 300 2 2003 4.9   2.6 0.15
  3 2006 3.0   2.6 0.15
300 < hp < 600 2 2001 4.8   2.6 0.15
  3 2006 3.0   2.6 0.15
600 < hp < 750 2 2002 4.8   2.6 0.15
  3 2006 3.0   2.6 0.15
             
175 < hp < 750 4 2011   0.3   0.01
             
hp > 750 2 2006 4.8   2.6 0.15
  4 2011 (gensets>1200 hp)   0.5   0.075
  4 2011 (all others)   2.6   0.075
  4 2015 (all gensets)     0.5    0.02
  4 2015 (all others)
2.6
0.03

Source: U.S. EPA, Control of Emissions of Air Pollution from Nonroad Diesel Engines and Fuel, June 29, 2004.

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